Fusion of Visual and Thermal Face Recognition Techniques: A ...

Figure 16 shows an example of detecting eyeglasses. In Figure 16, the first threshold
is used for face detection. The detection of faces is important to restrict the presence of
eyeglasses and reduce the searching area. After applying the first threshold, 70% of
eyeglasses are detected at the same time. In some cases as shown in Figure 16(b), the
threshlded images in the 1 st row are grouped together which result in incorrect eyeglass
detection. Although it fails in the 1 st threshold, the 2 nd threshold can detect the presence
of eyeglasses as shown in Figure 16(b) 2 nd row images. The optimal threshold can be
found after evaluation of the performance of the glass detection algorithm in terms of
False Acceptance Rate (FAR) and False Rejection Rate (FRR) as shown in Figure 17.
Eyeglasses
(a)
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